Collexis, a developer of search and discovery software, is acquiring the publisher of a legal research service for $9 million in cash, stock and future considerations.

Collexis, which trades its stock over the counter under the symbol CLXS, said Monday it would buy Lawriter, the publisher of Casemaker. Casemaker is based in Cincinnati.

Lawriter’s online services are used by law firms that include some 450,000 attorneys, according to Collexis. Twenty-eight state bar associations also contract with Casemaker.

“Our technology coupled with Casemaker’s content will certainly benefit Casemaker users,” said Bill Kirkland,chief executive officer of Collexis. “Over the next six to twelve months, Lawriter plans to introduce a Casemaker premium service and a suite of knowledge discovery and workflow tools.”

Casemaker is the oldest online legal publishing service, according to Casemaker founder Joe Shea.